Improvement in reproducing sound from records tracked by alpha stylus



A. HENDERSON Nov. 8, 1932.

IMPROVEMENT IN REPRODUCING SDUND FROM RECORDS TRACKED BY A STYLUS Filed Oct. 4, 1930 mum Ema/M fle/vomswv.

TTO/VEX Patented Nov. 8, 1932 :uNirE-oYsrArE's WILLIAM anmsraone nnnnnnsoiv, or NU HEAD. LON N, ENGLAND 'mlPROVEMENTTN BEPBODUCINGSOUND FROM' RECORDS TRACKED BY ASTY-LUS 'Applic'ation filed October 4, 1930; Serial No. 487,259, and in GreatBritain October .5, 1929.

Thisinvention relates to apparatus for reproducing sound from engraved records,-for instance, gramophones or electric relay pick up devices for use in conjunction with sound records in which a needleor its equivalent engages a sound record track. One, of the greatest objections to suchapparatus as at present employed isthe necessity to repeatedly replace the; needle or its equivalent and/or the rapid deterioration of the record by reason of the wear due to the friction of the needle.

ployinga-record track engagedbya needle of a soundbox or a thermionically relayed needle pickup device. The object of this invention is to remove or reduce these ob ections and also to improve the purity of the s D tothe zone of theneedle tip, for instanceon sound reproduced.

Broadly my invention is characterized by J the provision of means for supplying a friction absorbing or reducing medium to the point of the needle or its equivalent and/or to the sound track. I

Briefly my invention can be said to consist in utilizing a device for supplying a liquid having a low friction coefficient to the free end of the needle or its equivalent during the travel of the record whereby a restricted film of lubricating liquid is maintained at the needle point.

I have found by experiment that if the needle of a gramophone sound box is supplied with a very fine film of lubricating oil of low viscosity, for instance the best engine lubrieating oil, so that the oil trickles almost imperceptibly on to the sound record track, the

record does not deteriorate or become worn to a perceptible degree.

The lubricating oil can be supplied along the needle or to a point immediately in ad- Vance of the needle on the record, and any pose. For instance the needle can be supported in a stylus bar or aholderconstructed after the fashion of a smallstylus fountain pen, in

which a small tubular body accommodatesa charge of oil which trickles in an exceedingly fine quantity to the tip of theheedlefltbeing well known that the flow of oil will cease when there is a cessation of relative movement between the contacting needle and record.

Theneedle may be specially constructed so that it has a restricted central bore terminating at its lower end in a lateralopening near the point of the needle, the oil flowing along the needle from anysuitable source of supply,-for instance a small reservoir shaped toreceive the needleand to be connected to the stylus bar of sound box or the armature or needleholder'of a pick-up device. i Ifdesired thelubricating oil can be supplied from a reservoir attached to the sound box or pick-up device and supplying the oil to the-record immediately in a dvance of the needle, or as an exceedingly fine trickle onto. the exteriorof-theneedle near its point.

In order that my invention may be clearly understood and readilycarriedinto effect, Iv have appended hereto a sheet of drawings illustrating embodiments thereof and where.

in" V v Fig; 1 is aperspeetiveview of an adaptor for attachment to a gramophone soundljbox for. supplying'the oil to the needle.

- Fig.2 is a part seetionalsideelevation view,

showing the devieein use. I

Fig. 3 is-onerear elevation view of Fig. 2. ,Fig. 4 is a side elevation view showing the invention as applied to a device forlapplying the oil directly to the record. 1 v Figs. 5 and 6 showthe use of oil passages in the needles- Of Pick P ces or vg tm ophone sound boxes Referring to the drawing, in Figsfl 2 and .3, I have shown a smallcylindricaloih reservoir 2, closed bya screw cap 3 preferably r-having a milled periphery andif desired formed with a restricted air vent A. This reservoir is carriedbya U shapedibracket 5 which-by means of a set screwfi can be adj ustsuitable device may be employed forthis pur.- l

gbly zclamped to the periphery of the sound The base of the reservoir has extending from it a tube 8 the free end of which is located in juxtaposition to the needle 1. A capillary wick 9 fills the tube 8 and extends beyond each end of it, one end engaging the needle las shown in Fig. 2. By this means a continual supply of oil at a slow rate is fed to the needle 1 and trickles to the point of the needle. In practice the tube 8 and wick 9 will be as restricted in diameter as practical to ensure a very slow feed.

If desired, the oil may be fed-on to the record 10. just in advance of the. needle 1 as shown in Fig. 1, in which event the tube 8 with its projecting wick'9 shaped as a brush will be directed towards the record, the brush shaped end of the wick 9 engaging thereoor In Fig. 5 I have shown the armature 11 of a pick-up device fitted with an oil reservoir 12 and a filling hole'normally closed by a screw 18, the reservoir having a depending socket adapted to receive the needle 1 which is formed with one or more longitudinal grooves 15 along which the oil from the reservoir travels very slowly so as to accumulate on i and trickle from the needle point. In Fig. 6, a

similar arrangement is shown but in which instead of the channel or channels 15 the needle is formed with a restricted central bore :16 leading to the side of the needle point.

If desired the sound boX of a gramophone or the like can be specially constructed to store the lubricating oil, for instance by fitting into the tubular neck of the sound box a mica or other suitable disc to prevent oil from flowing along the tone arm, the interior of the sound box being filled with oil, and a sluitable conduit conveying the oil to the nee- The use of lubricating oil in the manner proposed does not injure the record, and in fact I find with the normal type of gramophone record the reverse applies, as the oil improves the record and its tonal value.

' My invention is useful in connection with cinematograph picture projection employing engraved sound records for reproducing ap-. propriate sounds, because at present considerable inconvenience arises out of the neces 'sity to fit a new needle for each record and to replace the record after afew uses.

What I claim is 2-- 1. In sound reproducing apparatus in which sound is reproduced by tracking a. record with, a needle a reservoir for'lubricating oil and a restricted passage leading fromsaid reservoir to the pointof the needle.

2. In a sound reproducing apparatus in which sound isreproduced by tracking a rec- 0rd with a needle a reservoir for lubricating oil and a restricted passage leading from said' reservoir to the point of the needle, said passage comprising a restricted bore or channel alon the needle.

3.?[11 sound reproducing apparatus in which sound is reproduced by tracking a record with a needle a reservoir for lubricating oil and a restricted passage leading from said reservoir to the point of the needle, a socket formed with said reservoir adapted to receive the needle, said socket being in the base of the reservoir.

4. In sound reproducing apparatus in which sound is reproduced by tracking a record with a needle a reservoir for oil and a small diameter tube leading from it to a point near the needle.

5. In sound reproducing apparatus in which sound is reproduced by tracking a record with a needle a reservoir for oil and a small. diameter tube leading from it to a point near the needle, a wick in said tube proJecting beyond the tube to a point contiguous to the needle.

6. In sound reproducing apparatus in which sound is reproduced by tracking a record with a needle a reservoir for lubricating oil and a restricted passage leading from said reservoir to the point of the needle, a socket formed with said reservoir adapted to 

